foul-smelling vs stinking

foul-smelling and stinking both are adjectives.

Word	Noun	Adjective	Verb	Adverb
foul-smelling	No	Yes	No	No
stinking	No	Yes	No	No

As adjectives, foul-smelling and stinking are synonyms defined as:

Other synonyms of foul-smelling include fetid, foetid, foul, funky, ill-scented, noisome, smelly.

foul-smelling (adjective)	stinking (adjective)
offensively malodorous	very bad
	offensively malodorous